Quitting at the top, Formula One champion Nico Rosberg shocked the world of motor racing Friday by announcing he was retiring at the age of 31, five days after earning his first world title.
"I have decided to end my Formula One career.

AVONDALE, Ariz. - After more than three hours of racing, NASCAR's championship field was decided over two frenzied overtime restarts.
Matt Kenseth probably should have won Sunday to earn an automatic berth into next week's title-deciding race.

SAO PAULO - Three-time series champion Lewis Hamilton won Sunday's rain-delayed Brazilian Grand Prix, forcing a showdown for the season title with Mercedes teammate Nico Rosberg in Abu Dhabi in the finale in two weeks.

AUSTIN - Nico Rosberg sat slumped in his chair, exhausted and exasperated after another race and world title was taken away by Mercedes teammate Lewis Hamilton. Then came the hat toss seen around the world.

UTICA, N.Y. - A federal judge ruled Friday that the insurance carrier for NASCAR driver Tony Stewart does not have to defend or indemnify him in a lawsuit brought by the family of a driver who died after being struck by Stewart's car during a race.
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INDIANAPOLIS - Dale Earnhardt Jr. will not race again this month because of concussion-like symptoms and the No. 88 car will be turned over to trusted former teammate Jeff Gordon for the next two weeks.

LOUDON, N.H. - Jeff Gordon is ready to pull his firesuit out of storage and come off the bench for one more shot at winning one of NASCAR's crown jewel races.
Gordon might not be done, but Junior just might be, at least for the immediate future.

SONOMA, Calif. - Tony Stewart sat slumped on the stairs inside his team transporter a year ago reflecting on the worst slump of his NASCAR career.
He had a migraine that day at Sonoma Raceway and spoke softly about his plight.

Route 66 Motor Speedway will host the first of six nights of the American Sprint Car Series National Speedweek Tour starting at 7 p.m. on Saturday and will be broadcast nationally on the MavTV network.

LAS VEGAS - Brad Keselowski passed Kyle Busch with five laps to go Sunday and surged to his second win in three years in the NASCAR race at the Las Vegas Motor Speedway under weird and windy weather conditions.

HAMPTON, Ga. - Jimmie Johnson smoked his tires crossing the finish line, celebrating another win at Atlanta Motor Speedway.
Then he realized what it really meant.
Johnson stuck his hand out of the No. 48 car, holding up three fingers.

DAYTONA BEACH, Fla. - Denny Hamlin burst onto the scene a decade ago when he showed up at Daytona International Speedway as a rookie and won the first exhibition race of Speedweeks.
Hamlin beat Dale Earnhardt Jr.

DAYTONA BEACH, Fla. - NASCAR has beefed up its punishment system and will define specific behavioral offenses with predetermined penalties.
The new system will serve as a personal conduct code for members in all three national NASCAR series.

DAYTONA BEACH, Fla. - Jeff Gordon will be in the booth and Tony Stewart in a bed when the NASCAR season begins.
Neither NASCAR star will be in a car when Daytona International Speedway opens today for preparations for the Feb.

CHARLOTTE, N.C. - NASCAR is expanding its Chase format to include its feeder series, meaning the champions from the Xfinity and Truck Series will now be crowned in a four-driver shootout at the season finale.

HOMESTEAD, Fla. - Denny Hamlin and Joey Logano, eliminated from title contention in earlier rounds of NASCAR's playoffs, played spoiler Friday by sweeping the front row for the season-ending race at Homestead-Miami Speedway.

KANNAPOLIS, N.C. - There was no final straw, no outside influence, no personal trauma that led Tony Stewart to set an expiration date on his NASCAR career.
Instead, the three-time NASCAR champion simply decided enough was enough.

There's a reason the four-driver organization could laugh off Kevin Harvick's blustered prediction that he not only will beatJoe Gibbs Racing in the Chase for the Championship, but that he will "pound them into the ground.

DARLINGTON, S.C. - Brad Keselowski won the pole for the NASCAR Sprint Cup race at Darlington Raceway, where he'll start up front for the first time all season while searching for his first Southern 500 victory.
Keselowski turned a lap at 178.

NEW YORK - A lawyer for a racecar driver who was killed when he was run over by Tony Stewart's car says legal claims by the NASCAR star in response to a lawsuit are "appalling."
Attorney Mark Lanier said Saturday in an email that Kevin Ward Jr.

BRISTOL, Tenn. - As Joey Logano circled Bristol Motor Speedway, he'd briefly glance in the mirror to watch Kevin Harvick.
Logano had taken the lead on a restart with 64 laps remaining, but Harvick was closing in by using a completely different line.